Mac enthusiast Dustin MacDonald explains, in a post titled “Why Inconsistency is Consistent,” why he feels that those “Mac fanatics” who complain about user interface inconsistency in Mac OS X applications go too far and ignore the fact that “being unique and different is a really good thing.”

He illustrates his point by providing screen shots of the original iTunes application window and of the main GarageBand project window and explains that their appearance makes the applications “easily distinguishable from others.”

I think that, to a degree, Dustin has a point. We do need visual clues that distinguish different things from each other. Otherwise, it would be too easy to get lost. And you could argue that, to a degree, the very similarities between applications in Mac OS X that give it its consistent look and promote familiarity can also be an obstacle.

In my job as a Mac helper, for example, I frequently encounter situations where inexperienced Mac users actually have no idea where they are. They are vaguely aware of the fact that every window has a parent application, but they do not always know what that parent application is, and part of the reason is that sometimes the only visual clue of what the parent application is is the menu heading of the application menu next to the Apple menu.

Granted, we are talking about very inexperienced users here. But there is no reason why these users should be treated with scorn and their needs should not be as important as anyone else’s. In that respect, the use of more obvious visual clues, such as the different look of the main iTunes or GarageBand application window, can be of significant help.

And, as long as the different look does not actually affect the usability of the application, it really does not make much sense to complain about visual inconsistency.

The new iTunes 7 interface is a pretty good example. It introduces a number of new custom controls that are markedly different from the standard Aqua controls used in previous versions of the software: the grey scroll bars and arrows, the grey column headings, the grey check boxes in song lists, etc.

But is there really a single Mac user out there who is confused by these changes? Is there really a single Mac user who won’t know that these grey scroll bars work just like standard scroll bars, that these grey column headings work just like standard column headings, etc.? It’s hard to imagine that there is such a user.

The actual standard here is not the exact look of these controls, but some key aspects of their appearance: the 3D effects that indicate something that can be clicked on, the shape of a box with a check mark in it, etc. When Apple moved from the standard “Platinum” look of Mac OS 9 to the “Aqua” look of Mac OS X, it introduced a number of standard UI features that are still very much in use today, even though the Aqua look itself has evolved, and Apple has since introduced a number of other looks.

The specific visual aspect of UI controls involves a number of factors beyond usability, and these other factors can dictate changes as long as these changes do not actually impact usability.

What is really irritating when you visit a web page that uses non-standard scroll bars or arrows is not the fact that they look different, but the fact that they behave differently, and usually in a way that severely impacts their usability, especially on the Mac. (These custom-designed controls are usually optimized for Windows.)

In the case of iTunes 7, on the other hand, the behaviour of the redesigned controls is exactly the same as the behaviour of the standard Aqua controls, so the change is only a matter of looks and visual distinction.

The fact is that there is consistency, and then there is consistency. Instead of complaining about changing looks, UI purists would do well to focus on inconsistencies that really do have an impact on usability. Such inconsistencies might be less obvious and less “glamorous,” but they are the ones that really do have an impact on daily use of Mac OS X in the real world.

One example is the difference between anchored selection and unanchored selection when selecting multiple items in a list. John Gruber at Daring Fireball provides a good overview of the distinction. Many Mac OS X applications, especially those designed by Apple, use unanchored selection, i.e. the selection grows in both directions and never shrinks. But there are also a number of important Mac OS X applications that still use anchored selection. Microsoft Excel is one example that comes to mind.

The problem here is that, from the user’s point of view, there is nothing that explains why selection should be unanchored in iTunes and Mail and anchored in Excel. And because of this, there is simply no way that the user can predict the behaviour and thus get used to the fact that the behaviour when selecting multiple items in a list changes depending on which application he is using.

Another example is the use of keyboard shortcuts for navigating or selecting blocks of text when editing text. It is simply impossible for me to get used to the fact that a shortcut such as option-Right does not cause the same behaviour depending on whether you are in Pages (or Word, Mail, and many other applications) or an Adobe product such as Photoshop or InDesign.

In Pages, Word, Mail, etc., option-Right moves the insertion point to the right by one word, whereas in InDesign it changes… the kerning. In InDesign, you have to use command-Right to move the insertion point.

Similarly, the option-Down shorcut moves down one paragraph in Pages, but it moves down one screen in BBEdit.

And I have also described elsewhere in this blog the new behaviour that Apple has adopted in its applications for text navigation keyboard shortcuts at the end/beginning of a paragraph. Here again, this behaviour only applies to Apple’s applications (Pages, TextEdit, Mail, etc.). In third-party applications, the behaviour of the same keyboard shortcuts is different.

If you are like me and use these kinds of shortcuts all the time, in all kinds of applications, then you know that it is simply impossible to get used to such inconsistencies.

One last example is the required delay when using drag-and-drop to move blocks of text around. In Microsoft Word 2004, as soon as you click on a selection and hold the mouse button down, you can drag the mouse pointer to drop the selection in a different location. In Pages or Mail, if you want to do the same thing, you have to wait for about half a second before you start moving the mouse pointer. If you move it too soon, then instead of dragging the selection, Mac OS X will actually change your selection altogether.

In all those situations, the problem is usually not that one behaviour is better than the other. It is the inconsistency itself, which has no justification other than the generally poor state of the software industry today. There is simply no real incentive for software developers such as Microsoft or Adobe to make a substantial effort to conform to Apple’s standards—and the fact that Apple keeps changing these standards does not help either.

As far as I am concerned, these inconsistencies are much worse in real-world computing activities than the purely visual inconsistencies that Apple introduces when it changes the look of an application such as iTunes. But until more users start being more vocal in their complaints about such inconsistencies, nothing will change, and we will have to continue to deal with them on a daily basis in our work.

3 Responses to “Mac OS X: The struggle for UI consistency”

I still find those new iTunes visuals distracting, not fitting in and rather ugly.

For the functional inconsistencies, I’d find your argument much more convincing if your examples were coming from software companies who care about UI, rather than Adobe and Microsoft who can’t even get the most trivial localisation right…

I fail to see how this makes the argument any less convincing. On the contrary, Microsoft and Adobe make some widely used applications, which means that a lot of people have to deal with these inconsistencies on a daily basis. (I suspect the situation is just as bad on the Windows side.) And, last I checked, Bare Bones Software was a company that did care about UI quite a bit—and still I cannot convince them to change the option-Down behaviour. (I’ve tried.)

As for the iTunes 7 controls, “distracting, not fitting in and rather ugly” are all rather subjective assessments. I agree that a situation in which each application had its own controls would be very confusing indeed, but we are quite far from that. Clearly iTunes is becoming a platform in its own right, almost a separate operating environment, so it’s entitled to its own visual identity.

I, for one, am glad that the top-right corner of the iTunes window no longer looks just like the top-right corner of any other brushed-metal application with a search field. This way, I will not click on that top-right corner by mistake thinking I am bringing a Safari or Finder window to the foreground or something.

Again, there is clearly a struggle between visual consistency and visual identity, but as long as we live in a computing world with application-centric approaches, giving these applications some kind of visual identity makes sense—as long as it doesn’t objectively affect usability in any significant way.

I’m in total agreement with you on this one, Pierre. Apple’s done a great job of making their visually distinctive applications functionally identical (the Pro Apps look, iTunes — not so much widgets). Windows apps have a long history of things just behaving any old way they want to, and that’s frustrating, but pure visuals just don’t have the same kind of negative impact.